Objective To establish a visual detection method of Salmonella based on recombinant enzyme polymerase amplification-CRISPR/Cas12a. Methods In this study, recombinase polymerase amplification (PRA) was combined with clustered regularly interspaced short palindromic repeats/associated protein 12a (CRISPR/Cas12a) system. RPA primers and CRISPR-derived RNA (crRNA) were designed and synthesized based on the target invA gene of Salmonella. Fluorescence and test strip methods were employed to read the results. The optimized RPA-CRISPR/Cas12 detection system were evaluated for specificity and sensitivity, and was applied to the detection of food samples. Results Nano gold test strip base on nucleic acid were developed. The established RPA-CRISPR/Cas12 detection method could specifically detecting Salmonella with a sensitivity of 80 CFU/mL within 1.5 h. Used this method to detect 21 kinds of food samples, the results from fluorescence and test strip read were consistent, with a Salmonella detection rate of 4.8%, which was completely consistent with the results of the national standard method. Conclusion The Salmonella RPA-CRISPR/Cas12a visual detection method established in this study has high specificity and sensitivity and is valuable for on-site rapid detection of Salmonella.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |